But when he got to Washington, the New Jersey Democrat had to start an official account from scratch, with zero followers.

That's because congressional ethics rules bar Booker and other lawmakers from transferring their personal or campaign followers to their official government Twitter accounts. The prohibition is in place because lawmakers aren't allowed to use office tools for campaign purposes.

Such rules reflect the growing challenge of coming to Washington in the digital age. Elected leaders must navigate an increasingly complex landscape to have the social media presence their constituents demand without getting in trouble.

To help make sense of it all, Twitter has invested in a Washington-based team to act as a liaison between the company and government entities that use the service. The group doesn't have any lobbyists or political agenda. Instead, this five-person contingent, which works with every level of government, from town mayors to the White House, serves the growing network of government entities for which Twitter has become a part of everyday life.

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On any given day, they walk the halls of Capitol Hill on their way to teach Senate communication directors how to use Twitter's latest tools, pass through security checks at federal agencies for a seminar with bureaucrats or host meetings at GOP or Democratic headquarters with campaign operatives.

Adam Sharp, a political and media veteran who formerly worked for Democratic Sen. Mary Landrieu and C-SPAN, leads the group from a small downtown office.

"Our role here is to help elected officials and agencies recognize that they can use the platform to communicate more effectively with constituents and give them ideas on how to do that," Sharp said.

Sharp was Twitter's first Washington employee in 2010, when he initially set up shop from his living room. At that point, Twitter had already been around for four years, but only about a quarter of Congress used the platform. Sharp's job at the time was spent mostly persuading government agencies and lawmakers to join.

Since then, Twitter has transformed the way Washington does business. In a town where information is traded like currency, Twitter's ability to share and spread a message has made it the first place many turn to break or find news. Nearly every government agency, from the Central Intelligence Agency to the U.S. Geological Survey, relies on the service, which they can use to reach their audience directly.

As Twitter's popularity grew throughout government and political circles, the company's mission here adapted. Their task shifted from persuading elected leaders to take a risk and try their site to teaching eager policymakers how to use it better.

Twitter's high-profile role has had an especially outsized role in reshaping the way Congress communicates with the media and constituents. In the weeks leading up to President Barack Obama's recent State of the Union address, Twitter's D.C. team was busy encouraging lawmakers to live-tweet their experience during the proceedings by posting their reactions, photos and videos using Vine, a camera app Twitter acquired in 2012. The pitch to members: Why wait for a television camera to find you when you can broadcast your personal response to the President of the United States in seconds?

The campaign paid off. Within minutes of Obama's remarks, congressional staffers and even lawmakers themselves pulled out smartphones to shoot brief videos throughout Statuary Hall — the room outside the House chamber that doubled as a media spin room after Obama's address -- of their bosses rebutting or praising the President's proposals. The House Republican Conference even set up a rapid response station to help automate the process for lawmakers who needed some extra help.

"We're moving toward a situation where members are letting people into the process and viewing it through their own eyes, which is a lot closer," said Sean Evins, a former House Administration Committee staffer who joined Twitter's government team in 2012. "You're seeing more members involved personally, and it brings a lot more people into the process."

Among high-level officials and agencies, the use of third-party technologies for messaging comes with risks, of course. In January, hackers broke into the official Twitter account of the U.S. Central Command and posted a warning message that claimed to be from ISIS, a terrorist group in the Middle East. The federal government quickly regained control of the account, but not before word and screenshots of the hack spread online.READ: CENTCOM Twitter account hacked, suspended

Sharp's team last year produced a handbook for policymakers on how best to use the platform, which along with security guidelines, recommends that policymakers use their accounts themselves to share photos and information about their lives and work. (Twitter is aiming to compete on photo-sharing with Facebook-owned app Instagram, which is currently dominating the online photo market.)

Of course, over-sharing can backfire. A website maintained by the watchdog Sunlight Foundation called "Politwoops" that tracks posts deleted by politicians serves as a graveyard of congressional digital mishaps. In January, freshman Republican Rep. Mike Bishop of Michigan tweeted photos from the House floor in violation of chamber rules that bar photography. He deleted them soon after. Last summer, several lawmakers removed tweets of praise for the release of hostage Sgt. Bowe Bergdahl once details of how the Obama administration handled the negotiations became known. Still, Twitter's D.C. reps hold that the opportunity to connect directly with constituents is well worth the risk.

"The best members of Congress who use Twitter are the ones who are using it themselves and using it in an authentic way," Sharp said. "It's not something to be afraid of. Opening this new gateway for that direct one-on-one communication gateway with constituents is something we haven't had in a long time."